Rotary cooler



April 15, 1941. A. w. LISSAUER ROTARY COOLER Filed Oct. 2, 1939 2 Sheets-Sheet 1 AEOLPH W LISSAUEQ,

g r N E? E ,5 v. 9 WW April 15, 1941. A, w. LISSAUER ROTARY COOLER Filed Oct. 2, 1939 2 Sheets-Sheet 2 E w 7 M Q V67 Z w W M w. m 0 A Patented Apr. 15, 1941 ROTARY COOLER Adolph W. Lissauer, Louisville, Ky., now by judicial change of name Arthur Wilmer Lissauer, assignor to Louisville Drying Machinery Company, Louisville, Ky., a corporation of Kentucky Application October 2, 1939, Serial No. 297,473

4 Claims.

Rotary coolers, for particulate materials such as starch, carbon, fishmeal, distillers grain, etc., are characterized by: a horizontally arranged rotary cylinder through which the initially hot particulate material passes in one direction, from the hot end to the cold end; and a bank of tubes, within the cylinder, through which the initially cold refrigerant passes in the opposite direction from a cold end inlet header to a hot end outlet header. In the fixed-tube type of cooler, the tubes remain stationary while the cylinder rotates, whereas in the rotary-tube type of cooler, to which the present invention generally relates, both tubes and cylinder rotate as a unit.

Rotary-tube types of coolers, with closed and open cooling paths, are respectively disclosed in U. S. Letters Patent #1,617,815 and #1,671,798. In the closed-path arrangement, the hot end of the tube bank is rigidly carried by and discharges into a closed rotary outlet header, which is mounted on the cylinder, while, in the open-path arrangement, it is loosely carried by a rotary supporting member or false header on the cylinder and discharges into an open stationary outlet header which is mounted adjacent the cylinder. The hot-end headers and associated parts of each cooler have the objection of being respectively expensive to fabricate. In addition, it obstructs the feed of particulate material into the cylinder. makes no provision for the longitudinal expansion and contraction of the tubes. On the other hand, the open-path arrangement permits discharged liquid to seep along the outside of the tubes, into the cylinder where it causes the particulate material to adhere to the tubes, thus forming a gummy deposit which eventually interferes with the operation of the cooler sufficiently to necessitate a shut-down for cleaning purposes.

The principal object of the present invention is to provide a rotary tube type of cooler having the advantages and avoiding the objections of both of the aforesaid open and closed-path arrangements.

More particularly, the important objects of the invention are to improve the design of the hot end of the cooler to the end of rendering it less expensive to manufacture, and more accessible for feeding purposes while accommodating the expansion and contraction of the tubes and avoiding seepage.

Another object of the invention is to render the flow-control valves, ordinarily mounted adjacent the discharge end of the tubes, more accessible.

The closed-path arrangement I An embodiment of the invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a side elevation of a cooler embodying my invention with the hot end broken away to show the construction and arrangement of the tubes and headers;

Figure 2 is an elevation of the hot end of the cooler, only two tubes being shown for the sake of clearness;

Figure 3 is a fragmentary section along line 33 of Figure l;

Figure 4 is a perspective view of the collecting hood associated with the outlet header;

Figure 5 is a longitudinal section of a portion of one tube; and

Figure 6 is a section along line 6-6 of Figure 5.

The rotary tube cooler illustrated in the drawings is conventional to the extent of having: a rotary drum or cylinder I, provided with particulate-material discharge openings 2 adjacent its cold end; a closed hollow inlet header 3 mounted on the cylinder at its cold end and provided with an axially directed pipe 4 through which a refrigerant, such as cold water, may be supplied to the header ii; a bank of tubes 5 within the cylinder; and a false header 6 mounted on the cylinder at its hot end and provided with an axial opening I through which particulate material may be fed into the cylinder. It will be understood that the tubes 5 are rigidly carried, at the cold end, by the inlet header 3 with which they communicate and from which they receive the refrigerant and that they are loosely carried, at the hot end, by the false header 6 in order to accommodate the longitudinal contraction and expansion of the tubes.

In accordance with my invention, the hot end of the tube bank is connected to discharge into a hollow ring-like outlet header 8 which is mounted adjacent the hot end of the cooler to rotate with the cylinder and which is provided with peripheral openings for the gravitational discharge ofthe refrigerant from the header. The hollow outlet header 8 may be located beyond the adjacent end of the cooler, in which event, its axial opening is made large enough to insure free access to the axial opening I of the false header 6. For the sake of convenience, compactness and economy, it preferably is mounted on the periphery of the cylinder l adjacent'to, but spaced somewhat inwardly from, the hot end thereof. The discharge end portions 5a of the tubes 5 are turned re-entrantly outward, that is to say, turned outwardly beyond the periphery of the cylinder I and thence longitudinally over the periphery, to extend into the outlet header 8 through suitable openings therein.

The liquid refrigerant discharged into the header 8 by the tubes 5 is prevented from splashing outwardly by means of an annular baifie 9 arranged Within the header 8 between its periphery and the discharge end of the tubes. This liquid passes gravitationally from the lower half of the header 3 through openings I0 formed, at intervals along the periphery of the header, by pressing vane-like portions inwardly from the periphery of the header. Where conditions permit, the liquid issuing from the header 8 may be permitted to fall directly upon the floor. Ordinarily, however, it will be desirable to confine the discharge and, for that purpose, a stationary collecting hood l2, having an outlet I3, may be arranged to extend around the lower half of the outlet header 8 and the associated end portions of the tubes 5.

With this arrangement, the end portions 5a, between the false header 6 and the outlet header 8, are completely exposed. Since they are thus rendered openly accessible, they are provided with fiow-control valves I4 by which the rate of flow through each tube may be manually regulated or adjusted.

Means are provided to create a high degree of turbulence within, and thereby insure a high heat-transfer rate along the working length of each tube, i. e. the length within the cylinder I. To this end, a rod I5, having a staggered series of horizontally spaced semicircular bafiles I6, is inserted within each tube to extend along its Working length.

A particular advantage of the foregoing construction is that its hot end, being completely unobstructed, permits the use of a horizontal conveyor for feeding particulate material to the cylinder through the opening 1. In addition, the

simplicity of its structure renders it correspondingly inexpensive to manufacture, the accessibility of its valves l4 makes it easy to regulate, the arrangement of its headers 6 and 8 accommodates the expansion and contraction of the tubes while avoiding seepage of the refrigerant into the cylinder, and the tube insert insures minimum cooling tube temperatures.

Having described my invention, I claim:

1. A cooler of the rotary-tube type comprising: a rotary cylinder having hot and cold ends; a tube bank within the cylinder; inlet and false headers respectively mounted on the cylinder adjacent its cold and hot ends; and a hollow outlet header mounted on the periphery of the cylinder adjacent the hot end thereof to rotate therewith, said header having discharge openings; the discharge end portions of the tubes in said bank being turned re-entrantly outward to discharge into said outlet header.

2. The cooler defined in claim 1, wherein: the discharge end portions of said tubes are provided with flow-control valves.

3. A cooler of the rotary-tube type comprising: a rotary cylinder having cold and hot ends; an inlet header mounted on the cylinder adjacent its cold end; a false header mounted on the cylinder adjacent its hot end; a hollow ring-like outlet header mounted on the periphery of the cylinder adjacent the hot end, said header having peripheral discharge openings; and a series of tubes extending from the inlet header through the cylinder and the false header and then turning re-entrantly outward to discharge into said outlet header.

4. The cooler defined in claim 3, wherein an annular splash-restricting battle is positioned within said outlet header between the peripheral discharge openings and the discharge area of said tubes.

ADOLPI-I W. LISSAUER. 

